The cytopathologic characteristics as seen in fine needle aspirate smears of 50 thyroiditis patients were reviewed, with emphasis on pitfalls. Fortyeight patients were female and only 2 patients were males. Of these, 46% were in 4th decade of life. Fifty two percent came within a period of 6 months of illness of which 46.15% were hypothyroid at presentation. The cytologic diagnoses were as follows : Hashimotos thyroiditis (H.T.) 13; lymphocytic thyroiditis (L.T.) 11; subacute thyroiditis 2; acute thyroiditis 1; and suspicious benign lesions 23. Thirty patients were operated. Twenty three erroneous diagnoses were uncovered by (i) repeat FNA in 3 cases (ii) smear examination by single senior cytopathologist in 8 cases and (iii) histopathological examination of operated thyroid specimen in 12 cases. Prerequisites for accurate cytological diagnosis is adequate and representative sample. Cytodiagnostic pitfalls occured mainly in cases of H.T. Examination of FNA slides of suspicious thyroiditis cases by single senior cytopathologist was the key factor in achieving diagnostic accuracy. The ease of doing FNA and its diagnostic accuracy mandate continued use of FNA in the diagnostic management of patients with thyroidits.

FNA was performed on 103 cases of bone lesions inclusive of 66(64.1%) primary lesions and 37(35.9%) metastatic deposits. Out of the 66 primary lesions, 60(58.3%) were diagnosed as malignant tumours; 42 out of the 60 had histopathologic examination of which 40 were confirmed. Thus the overall diagnostic accuracy of FNAC of primary malignant tumours was 95.2%. Giant cell tumours constituted the highest number (20.4%). The 37 metastatic tumours included primaries from various sites. Out of these histopathological examination was done in 12 and the diagnosis confirmed in 11 giving a diagnostic accuracy of 91.6% for FNAC of secondary tumours. Thus FNAC was found to be extremely useful in the preliminary diagnosis of bone lesions.

Rapid diagnosis was made on 51 breast lumps by imprint, fine needle aspiration (FNA), non aspiration (NA) and aspirate centrifugation methods in sequence and the results compared with those obtained by paraffin histopathology - Quality of smears obtained by different cytological techniques were compared by using a point scoring system, described by Mair et al. It was found that blood contamination was least in NA than all other cytological techniques but amout of cellular material obtained was higher with FNA & imprint. Regarding the other features like amount of cellular degeneration, cellular trauma & maintenance of architecture, no significant difference was observed. It was observed that diagnostic accuracy was more in imprint followed by FNA. Quality of smear was good in NA, followed by imprint. The aspirate centrifugation results were poor in quality as well as in diagnostic accuracy.

FNAC smears from 19 selected cases of lytic lesions of bone which were clinically, radiologically and histogically confirmed to he Langerhans cell histiocytosis were selected for study of cell population by differential count in the smear. Radiologically two types of lesions were observed, lytic lesion and lytic lesion with sclerotic border (aged lesion). The differential count revealed a predominance of eosinophils closely followed by neutrophils; mononuclear giant cells with nuclei like that of Langerhans cells comprised 10% only, though this cell is the characteristic cell for Langerhans cell histiocytosis. A correlative differential count in two radiological types (lytic lesion and the lytic lesion with sclerotic border) revealed that lytic lesions were more densely populated by eosinophils against the aged lesions having more of neutrophils, multinucleated giant cells and foamy giant cell. Thus the diagnostic problem by FNAC arises when one observes :

• the neutrophil cell population exceeds the eosinohpil population.
• scanty mononuclear giant cells, and more of foamy giant cells.

FNAC findings need to be correlated with clinical and radiological findings to arrive at a diagnosis, in absence of special stains and EM facility.

Intracystic papillary carcinoma (ICPC) of the breast is a rare tumour described in females. We report a case of ICPC of breast in a 25 year old male diagnosed by fine needle aspiration cytology. ICPC has distinct cytology features and can be diagnosed by fine needle aspiration cytology (FNAC).

Wegener's granulomatosis is a form of necrotizing vasculitis. Radiological examination, open lung biopsy and Anti-neutrophil cytoplasmic antibodies (ANCA) are the standard methods to arrive at a diagnosis. Experience with fine needle aspiration diagnosis are however limited. We herewith present one such case report where the diagnosis was suggested primarily by FNAC and subsequently confirmed by anti-neutrophil cytoplasmic antibody (ANCA) positivity thus obviating the need for an open lung biopsy.

Disseminated endometriosis is an uncommon condition that may be clinically confused with widespread malignancy. Here we report our experience with a case of widespread endometriosis of pelvis and omentum in which fine needle aspiration cytology (FNAC) was instrumental in making the diagnosis.

Giant cell tumor of tendon seath (GCTTS) is slow-growing, well-circumscribed nodule arising from the synovial membrane lining cells. We studied FNA smears of a series of six cases. The cytologic pattern was diagnostic of GCTTS in all the six cases, which was confirmed by histopathologic examination. The cytologic findings suggesting a diagnosis of GCTTS include high cellularity, a large number of multinucleate giant cells, a prominent population of mononuclear cells occurring singly, and the presence of stromal hyalinisation, hemosiderin-laden macrophages, vacuolated cells and a few histiocytes in the background. Stromal hyalinisaton which was noted in 4 cases has not been yet described in cytology material.